Step2 : First try to reset the password from clicking on the Can’t access your accountSteps 3 : Try to reset your administrative password.Steps 4 : Please open the secondary email as you have keep when you have created this google apps email account.
Open the Email account and click on the link and reset your google apps admin password.

If you are not able to accessing the google apps secondary Email, please try to follow the second option
to verify the google code

In the second option you have to create the CNAME record under your hosting panel .
Google provide you the code you need to create the name with google code and point to google.com

After creating the CNAME record you need to click on the verify also you can open on the given link which
has redirected to the google.com

Now after verification you can login to your account with same password and please follow the below steps
to downgrade your google apps business to free account.Sign in to the Google Apps administrator control panel.
The URL is https://www.google.com/a/cpanel/primary-domain-name, where primary-domain-name is the domain name you used to sign up for Google Apps.
Click Domain settings.
Click the Subscriptions & Billing tab.
Click the Cancel Google Apps for Business link. (This link appears only when your Google Apps for Business trial account has 10 or fewer users (the Google Apps free edition limit). If your account has more than 10 users, you must end the trial and begin your subscription.)

or it has degrade you under stander account.

and click Yes, cancel the free trial.
This change may take up to 30 minutes to take effect.